Method for manufacturing pottery ware



1937- w. J. MILLER 2,091,767

METHOD FOR MANUFACTURING POTTERY WARE Original Filed July 14, 1933 2 Sheets-Sheet 1 3nnentor 5-2111;- a W// //am Mi/lcrn Aug. 31, 1937. w. J. MILLER METHOD FOR MANUFACTURING POTTERY WARE Original Filed July 14 1933 2 Sheets-Sheet 2 ZSnventor W/'///a 711 Li M /'//6 r the wen-aria by "the" veiume Patented Aug. 31, 1937 UNITED STATES PATENT OFFICE William J. Miller, Swissvale, Pa.

Original application July 14, 1933, Serial No. 680,483. Divided and this application May 6,

1935, Serial No. 19,990

13 Claims. (Cl; 25-156) This invention relates to. the manufacture of high quality table pottery ware, such as plates, cups and saucers and more particularly to improved methods and means for segregating charges of clay from a mass, p-reshaping blanks therefrom and applying, securing and shaping the blanks on absorbent molds for subsequent jiggering to final finish and polish.

This application is a division of my co-pending application for United States Letters Patent S. No. 680,483, filed July 14, 1933, for Method of and apparatus for the manufacture of potteryware.

The objects are to reduce manual labor required; insure continuity of production; reduce clay wastage and the percentage of defective ware; improve the quality and quantity of the ware produced and generally reduce production costs.

The methodcontemplates the steps of supplying at convenient, and if desired, irregular intervals, semi-conditioned clay masses to a reserve hopper; progressing it into and through conditio'ningglcplumn forming and progressing apparatusi measuring ,and severing predetermined 25 lengthslugs therefrom each containing a multivple'of charges, toprovide a reserve supply; determining the'slug length, instant of and frequency of slug production by the volume of clay fwithdrawnfiin the production, of a multiple of 30 smoothing the" weld; successively severing porj i tions from the slug and controlling'the volume of j 'eachportion 'by the volume withdrawn'in preceding charge'forming operations; depositing the f portionsin a stabilizingreserve well; applying a substantial pressureft'o the clay"in the"we1l to ema emetiit 1 h si i ere 'a charges; welding the slug ends together and ntrollingithe er clay thereto m ofthe reserve supply'remainin in by the e I bearing a distinct relation to the finished ware;

segrega n'g apparatus D};

ater-charms f fach 's'urf ace of in? h di a in? "P., i a in "Shaped permeable'form bysu'ction 'througlfthe mm while transferring and applying the blank to the surface of an absorbent or permeable mold; applying and securing the blank in predetermined angular position and uniform concentric bulk distribution to the mold while held by said form; progressively spreading the blank over the mold from center to periphery by pressing it between the-form, a stationary permeable matrix; and a movable absorbent and/or permeable mold until the bri nis extended, the surface contoured and the thickness'established to substantially'coin cide with that of the finished ware; repelling the shaped ware from the matrix and form by forcing air under pressure through the permeable walls of the matrix and form, and suction to the under side of the mold, 'substantiallyat the instant of recession of mold from matrlxand form; transferring the mold and shaped ware to a finishing station; rotating the shaped ware surface secured to the mold against a profile tool to finally finish and polish 'the surface and brim, thereafter drying the ware while still on the mold.

In the drawings:

'Figure' 1 is a sectional elevation on line I-I, Fig. 2, showing the 'main parts of an apparatus embodying pm y invention;

Fig. 2 is a plan view of the apparatus?" Fig. 3 is a detail of a retarder fortheifeeder' belt of the apparatus; f I 1 Fig. 4 is al'sec'tion online IV- -IV, Fig. 2; and

Fig. 5 is anenlarged View of a portion of Fig. 1.

In Figs. 1,?1 and 5, I show a frame A with cross members 13 'provided Withaseries of-accurately spaced holes B'I for ddwelsby whicnare' secured and extruding apparatus a; slug measuring and a claysupply-reserve or and cdnipactihg device E, a-charge ple of parallel'lines-of production.

ys :2 are to a position a'djacentthe' apparatus zH ahd M to and positioned onthe fra'nie, acondition-ing houses" "nibld conveying apparatus a toggle joint 9, 9a, operated through a link In by a cam Semi-conditioned clay is fed into a hopper l3 and finally conditioned in the screw extruder C, then progressed through a die M as 5 a column by means of an electric motor l5 controlled by relay I6, contacts l1, I8 and anchor switch I9, said motor driving the screw of the extruder. When a' belt 20 advances the column 2| a predetermined distance, cam 22 rotating in 1,0 unison with the belt 20 lifts the anchor L9 and operates a cutter 23 to part and release a slug of predetermined length from the tail 24 of the column in the die l4 and permit it to gravitate on rollers 25 towards, collide with and weld to the preceding slug 21 (Fig. 5), the weld being smoothed when drawn between rollers 21a; further progression of belt causes a. pin 26 on cam 22 to shift the anchor l9 to right against the contact l8 to start the motor l5 and extrude 20 a fresh column of clay over rollers until the end contacts with and shifts anchor l9 to left against adjustable contact H to stop motor l5 and extruder C.

Thusclay slugs are extruded, severed and 25 conveyed by measuring device D at the same rate as used by the reserve of stabilizing device E. The conditioning deviceC, slug forming device D, and stabilizing device E, together, provide a reserve clay supply to insure uninterrupted operation. To control the intensity of impact between slugs 2| and 21, rollers 25 are connected with retarders, for example fluid pumps, Fig. 3, having the circulation restricted by a valve 28.

A crosshead 29 is reciprocated vertically on guides 30 by cam through link I0, crank 9a and link 91) and through bolts 3|a carriesa plate 3| which houses a bushing '32 in threaded engagement therewith. A housing 33 fixed to the frame A has a rectangular reserve well 34 in which a ram 35 is reciprocated by the plate 3| through a stem 36, the adjustable bushing 32, nuts 31, and a spring 38. A bracket 39 secured to stem 36 loosely embraces and reciprocates a rack bar 4| which engages a gear 42 driving a roller 43 through internal ratchetand pawl (not shown) to progress the belt 20 and slug 21 intermittently to left only. A spring 41 and nuts threaded on the bar 4| provide a resilient and adjustable stroke of the same.

As ram 35 descends it shears off protruding end of slug 21, and progresses the clay through a port 44 into a circular chamber 45 of the disk shaped turret K having teeth 46 for its rotation, until the chamber 45 is filled, then spring 38 yields, thus arresting descent of the ram 35 and rack 4|; meantime, a pawl 4|1'on a stem 46a has locked the gear 42 to temporarily prevent advance of slug 21. Upon elevation of crosshead 29, the spring 41 is compressed leaving the 0 rack 4| stationary until at the end of the elevation of the bracket 39 it lifts the stem with the pawl 40. The spring 41 then advances slug 21 to the extent to which the ram 35 has descended, so that as less clay remains inthe well, more 5 clay is deposited therein, and vice versa. As ram 35 descends, a former 48 is elevated into the chamber 45 through a lever 49 and pitman 50 actuated from the plate 3|, a predetermined distance adjustable while in operation through a 7 screw similar to screw 5|, Fig. 4. The former determines the diameter, lower contour and bulk of the charge, and it enables the chambers 45 in the turret to be filled to less than capacity by any desired extent. After retraction of the former 46 a one-way rack pawl 52 operatedby the lever 4 and pivoted to crossbar 53, engages the teeth 46 of turret K to turn in counterclockwise by one division to shear the charge from the mass by the action of. a' grid 44a, and carry it to a preforming position G. A look 54 operated by the pawl 52 at the termination of its travel locates and holds the turret 46 stationary, while an upper former 55, Fig. 4, and a lower former 56, advance into the chamber 45 to contour both surfaces of the blank 51, the degree of pressure applied being adjustable through nuts 58 and spring 59 on a pitman 59a. Replaceable bushings 51a facilitate substitution. of various brim shape and diameter blank formation, and exchangeable liners 511) between the housing and its removable base 33a facilitate substitution of various length bushings, whereby the effective depth of the chamber may be varied.

Blank 51 is next brought under a final former 66 adapted to enter the chamber 45 when it reaches position H where the blank is transferred, conformed and secured to the surface of the mold through matrix l2 and the former 60. Former 60 is reciprocated by the crosshead 29 through a hollow stem 600. which extends through a bushing 60band is threaded and grooved for applying a nut 600 above, and a pressure relief collar 60d below the bushing 60b. Collar 600? houses a series of adjustable spring pressed balls 60c which seat in the groove of stem 60a. When excess pressure is applied they release, thus controlling maximum pressure application and also avoiding breakage. Bushing 60b serves to adjust the lowermost extent of travel of former 50 thereby determining the thickness of the central portion of the formed ware and the threaded stem of the chuck 1 determines the thickness of receiving said stem. At position J, chamber 45 may be cleaned and treated to prepare it for a subsequent charge. Thereafter mold is transferred to final finishing and polishing apparatus. The faces of the blank are preferably contoured convex to facilitate spreading and to insure against entrapping air between the clay and the mold, avoid folds, etc.

The clay contacting faces of matrix l2, ram 35, formers 48, 60, 55, and 56 are of permeable material and their opposite faces are chambered and in communication with a source of suband superatmospheric pressure, controlled by adjustable cam operated valves not shown, to control clay adhesion to and repulsion from these surfaces. During transfer ofv the blank from chamber 45 to mold l, sub-atmospheric pressure may be admitted through the face of former 60 to attract and hold the blank thereto, thus insuring proper blank placement. Also, by applying subor superatmospheric pressure of predetermined pressure, the instant and duration of application to the clay through the permeable faces of formers 48, 55, 56, and 60, during and/or following the forming operation, the water content of each face of the blank may be predetermined prior to application to the mold.

Wheresoever the term pressing or derivatives shall occur in the appended claims with respect to the shaping of clay it shall mean the co-operation of co-extensive surfaces forming therebetween a cavity in which clay is subjected to forces in compression. Wheresoever in the appended fclaims the term spreading shall occur with respect to the application of clay to a mold, it

shall mean a radial flow of the clay in all directions simultaneously over the surface of the mold as by squeezing between relatively. movable surfaces.

The formers are arranged to extract moisture particularly during transfer from one position Y .shapeand size and regular outlined brim, ap-

to another when suspended by its brim. 0bviously, the extraction of water will shorten the subsequent drying time required.

The blank brirn is compacted against and defined and supported by the chamber wall to facilitate transportation and concentric application to the mold without distortion, thus insuring uniform radial spread and final concentric regular outlined brim in the formed ware, the large diameter and thin regular section also contributing towards said result. I thus dispense in the subsequent jiggering operation, with trimming oil" and discarding the irregular excess brim resulting from applying irregular compact unformed charges, unguided, direct to the mold. The jiggering operation referred to is for the purpose of finishing and polishing the exposed surface of the shaped ware surface. in the art is the final step in the profiling operation accompanied by slurrying the material to produce a smooth final finish and polish and the operation does not entail the removal of excess material.

While I have shown and described the preferred embodiment of my invention, I wish it'to be understood that I do not confine myself to the precise details of construction herein set forth, by way of illustration; it is apparent that many changes and variations may be made therein, by those skilled in the art, without departing from the spirit of the invention, or.exceeding the scope of the appended claims.

I claim: 1. In the manufacture of pottery ware, the method of forming clay charges which consists in compacting clay from a source of supply into a closed chamber, determining the bulk of the charges by regulating the depth of the chamber, severing each successive charge from its soprce of supply, and then shaping the charge to approximateware shape independently of the mold on which the ware is finally finished.

2. In the manufacture of potteryware, the method which consists in extruding, clay in the form of a column, severing the column into suitable lengths, successively severing portions adequate for the making of a plurality of ware pieces from the forward end of the lengths and compacting the portions so severed into a confined mass, severing successive charges from the mass,

shaping the charges, and transferring the charges to molds preparatory to shaping and finishing the charges into ware.- I

3. Method of making pottery ware comprising 7 segregating a measured charge of predetermined bulk from a mass of conditioned clay, moulding the charge on all surfaces into a blank having predetermined brim and faces and shape and size approaching those of the finished ware and 7 thereafter applying the blank to a mold.

This may Finishing or polishing 4. A method according to claim 3' including the step of profiling to polish the same.

5. The method of manufacturing pottery ware which comprises, forming a body containing a multiple of mold charges, reducing the body to a plurality of individual charges of relatively thin substantially disk-like proportions, applying each charge centrally to a mold on which the ware. is

to be -jiggered, pressing the charge to spread the same completely over the ware-forming surface and to full ware diameter, and thereafter profiling the exposed surface thereof.

6. The method of fabricating pottery ware. which comprises, forming a charge of clay on all surfaces into a blank having a.predetermined plying the blank and securing it to a mold, pressing the blank thereagainst until the brim is extenddto full diameter, the surfacefinally contoured and the thickness established to substantially coincide with that of the finished ware and thereafter subjecting the mold and ware to a drying atmosphere.

7. The method of fabricating dinnerware which comprises, forming a charge of clay into a blank of predetermined shape and size, extracting fluid from the clay, applying the blank in predetermined angular position to a mold, pressing the blank on the mold to extend the brim and contour the surface of the blank, profiling the blank to finish and polish the surface and thereafter drying the clay whilst still retained on the mold.

8. The method of fabricating pottery ware which consists in, forming a clay blank having a predetermined shape and size, applying the blank to a mold, pressing the blank between the mold and a stationary matrix to extend the brim to full ware diameter, repelling the clay from the matrix, jiggering the clay to finish and polish the same and thereafter drying the clay whilst still on the mold.

9. The method of fabricating pottery ware which consists in, forming an undersized clay blank, applying the blank in predetermined angular position to a mold and securing the same thereto, progressively spreading the blank over the mold from center to periphery by stationary permeable matrix until the brim is extended to full ware diameter, repelling the clay from the matrix by forcing air under pressure through the permeable walls of the matrix whilst applying suction to the under side of the mold substantially at the instant of recession of the mold from the matrix and thereafter finishing the exposed surface of the clay and drying the same whilst retained on the mold.

l0. The method of fabricating pottery ware which consists in, forming an undersized clay blank, transporting the blank whilst suspended by its brim to a position concentric with the ware forming siinface of a mold, applying the blank to the mold and expanding the same, limiting the degree of expansion on the mold t the. area of the ware forming surface "of the m ld, jiggering at least one surface of the clay and thereafter drying the same.

11. The method of fabricating pottery ware which consists in producing a clay charge having "a minimum of surplus material and then molding this charge into a thin section blank, applying the blank to a mold and expanding the blank to fully cover the ware forming surface of the mold whilst confining the blank thereto and thereafter drying the clay on the mold.

12. A method of making pottery ware which consists in shaping a clay mass having a volume of material therein equal to one mold charge into a disc having definitely outlined brim and contoured faces, laying the disc on the ware forming surface of a mold, the disc occupying a position from whence it may be spread in all directions equi-distantly upon the application of an expanding force and thereafter pressing the clay to expand it to full ware diameter and cause it to flow over the ware forming surface of the mold and then jiggering the clay.

13. A method of manufacturing pottery ware jiggering the mold m 

